"two make up all natural occurrence of lithium on Earth, although further isotopes have been synthesized. In ionic compounds, lithium loses an electron to become positively charged, forming the cation Li. Lithium is the first alkali metal in the periodic table, and the first metal of any kind in the periodic table. At standard temperature and pressure, lithium is a soft, silver-white, highly reactive metal. With a density of 0.564 g·cm, lithium is the lightest metal and the least dense solid element. Lithium is one of the few elements synthesized in the Big Bang, making it a primordial element. Lithium"
"only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm is sometimes quoted as a commonly used criterion and is used in the body of this article. The earliest known metals—common metals such as iron, copper, and tin, and precious metals such as silver, gold, and platinum—are heavy metals. From 1809 onwards, light metals, such as magnesium, aluminium, and titanium, were discovered, as well as less well-known heavy metals including gallium, thallium, and hafnium. Some heavy metals are either"
"lighter still. Tube-based nanostructures are similar structures on a smaller scale. Metallic microlattice A metallic microlattice is a synthetic porous metallic material consisting of an ultra-light metal foam. With a density as low as 0.9 mg/cm (0.00561 lb/ft), it is one of the lightest structural materials known to science. It was developed by a team of scientists from California-based HRL Laboratories, in collaboration with researchers at University of California, Irvine and Caltech, and was first announced in November 2011. The prototype samples were made from a nickel-phosphorus alloy. In 2012, the microlattice prototype was declared one of 10 World-Changing Innovations"
"and the radioisotopes present a significant health and ecological hazard in the environment. Caesium is the softest element (it has a hardness of 0.2 Mohs). It is a very ductile, pale metal, which darkens in the presence of trace amounts of oxygen. When in the presence of mineral oil (where it is best kept during transport), it loses its metallic lustre and takes on a duller, grey appearance. It has a melting point of , making it one of the few elemental metals that are liquid near room temperature. Mercury is the only elemental metal with a known melting point"
"materials could mass less than 0.1 g/m, making them lighter than any current sail material by a factor of at least 30. For comparison, 5 micrometre thick Mylar sail material mass 7 g/m, aluminized Kapton films have a mass as much as 12 g/m, and Energy Science Laboratories' new carbon fiber material masses 3 g/m. The least dense metal is lithium, about 5 times less dense than aluminium. Fresh, unoxidized surfaces are reflective. At a thickness of 20 nm, lithium has an area density of 0.011 g/m. A high-performance sail could be made of lithium alone at 20 nm (no"
"environment. Lithium is the metal with lowest density and with the greatest electrochemical potential and energy-to-weight ratio. The low atomic weight and small size of its ions also speeds its diffusion, suggesting that it would make an ideal material for batteries. Experimentation with lithium batteries began in 1912 under G.N. Lewis, but commercial lithium batteries did not come to market until the 1970s. Three volt lithium primary cells such as the CR123A type and three volt button cells are still widely used, especially in cameras and very small devices. Three important developments marked the 1980s. In 1980 an American chemist,"
"have a metallic radius of only 158 pm, very close to that of the much lighter magnesium, despite its expected atomic weight of around 474 u which is about 19.5 times the atomic weight of magnesium. This small radius and high weight cause it to be expected to have an extremely high density of around 46 g·cm, over twice that of osmium, currently the most dense element known, at 22.61 g·cm; unhexquadium should be the second most dense element in the first 172 elements in the periodic table, with only its neighbor unhextrium (element 163) being more dense (at 47"
"literally translated into ""little silver"". It is a dense, malleable, ductile, precious, gray-white transition metal. Platinum has six naturally occurring isotopes. It is one of the rarest elements in the Earth's crust and has an average abundance of approximately 5 μg/kg. It is the least reactive metal. It occurs in some nickel and copper ores along with some native deposits, mostly in South Africa, which accounts for 80% of the world production. As a member of the platinum group of elements, as well as of the group 10 of the periodic table of elements, platinum is generally non-reactive. It exhibits"
"Lithium Lithium (from ) is a chemical element with symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the lightest metal and the lightest solid element. Like all alkali metals, lithium is highly reactive and flammable, and is stored in mineral oil. When cut, it exhibits a metallic luster, but moist air corrodes it quickly to a dull silvery gray, then black tarnish. It never occurs freely in nature, but only in (usually ionic) compounds, such as pegmatitic minerals which were once the main source of lithium. Due to its solubility"
"lighter for the same conductance. Silver, although it is the least resistive metal known, has a high density and performs similarly to copper by this measure, but is much more expensive. Calcium and the alkali metals have the best resistivity-density products, but are rarely used for conductors due to their high reactivity with water and oxygen (and lack of physical strength). Aluminium is far more stable. Two other important attributes, price and toxicity, exclude the (otherwise) best choice: beryllium. (Pure beryllium is also brittle.) Thus, aluminium is usually the metal of choice when the weight or cost of a conductor"
"this latter term has more recently been discouraged by Atkins et al. as it has a different meaning in physics—one that more specifically refers to the electronic band structure of a substance rather than the overall classification of an element. The most recent IUPAC publications on nomenclature and terminology do not include any recommendations on the usage of the terms metalloid or semimetal. Pure boron is a shiny, silver-grey crystalline solid. It is less dense than aluminium (2.34 vs. 2.70 g/cm), and is hard and brittle. It is barely reactive under normal conditions, except for attack by fluorine, and has"
"Metallic microlattice A metallic microlattice is a synthetic porous metallic material consisting of an ultra-light metal foam. With a density as low as 0.9 mg/cm (0.00561 lb/ft), it is one of the lightest structural materials known to science. It was developed by a team of scientists from California-based HRL Laboratories, in collaboration with researchers at University of California, Irvine and Caltech, and was first announced in November 2011. The prototype samples were made from a nickel-phosphorus alloy. In 2012, the microlattice prototype was declared one of 10 World-Changing Innovations by ""Popular Mechanics"". Metallic microlattice technology has numerous potential applications in"
"metals close to the metal-nonmetal borderline. These metals behave chemically more like the metalloids, particularly with respect to anionic species formation. The nine chemically weak metals identified by them are beryllium, magnesium, aluminum, gallium, tin, lead, antimony, bismuth, and polonium. Cardarelli, writing in 2008, categorizes zinc, cadmium, mercury, gallium, indium, thallium, tin, lead, antimony and bismuth as fusible metals. Nearly 100 years earlier, Louis (1911) noted that fusible metals were alloys containing tin, cadmium, lead, and bismuth in various proportions, ""the tin ranging from 10 to 20%."" Van Wert grouped the periodic table metals into a. the light metals; b."
"small size of the difference in density and difficulties in measuring it accurately, but, with increased accuracy in factors used for calculating density X-ray crystallographic data yielded densities of 22.56 g/cm for iridium and 22.59 g/cm for osmium. Iridium is the most corrosion-resistant metal known: it is not attacked by almost any acid, aqua regia, molten metals, or silicates at high temperatures. It can, however, be attacked by some molten salts, such as sodium cyanide and potassium cyanide, as well as oxygen and the halogens (particularly fluorine) at higher temperatures. Iridium forms compounds in oxidation states between −3 and +9;"
"is elevated by 200–300 K. An oxygen-free atmosphere is not necessary for machining operations. Magnesium alloy Magnesium alloys are mixtures of magnesium with other metals (called an alloy), often aluminum, zinc, manganese, silicon, copper, rare earths and zirconium. Magnesium is the lightest structural metal. Magnesium alloys have a hexagonal lattice structure, which affects the fundamental properties of these alloys. Plastic deformation of the hexagonal lattice is more complicated than in cubic latticed metals like aluminium, copper and steel; therefore, magnesium alloys are typically used as cast alloys, but research of wrought alloys has been more extensive since 2003. Cast magnesium"
"Iridium Iridium is a chemical element with symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, iridium is the second-densest metal (after osmium) with a density of as defined by experimental X-ray crystallography. However at room temperature and standard atmospheric pressure, iridium has a density of , higher than osmium measured the same way. It is the most corrosion-resistant metal, even at temperatures as high as 2000 °C. Although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can be flammable."
"differences become less clear at the boundaries. Light structural metals like beryllium, scandium, and titanium have some of the characteristics of heavy metals, such as higher melting points; post-transition heavy metals like zinc, cadmium, and lead have some of the characteristics of light metals, such as being relatively soft, having lower melting points, and forming mainly colourless complexes. Heavy metals are present in nearly all aspects of modern life. Iron may be the most common as it accounts for 90% of all refined metals. Platinum may be the most ubiquitous given it is said to be found in, or used"
"Caesium Caesium (IUPAC spelling) or cesium (American spelling) is a chemical element with symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28.5 °C (83.3 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium and potassium. The most reactive of all metals, it is pyrophoric and reacts with water even at −116 °C (−177 °F). It is the least electronegative element, with a value of 0.79 on the Pauling scale. It"
"series, (lanthanum (920 °C) – lutetium (1622 °C)) to the extent of hybridization of the 6s, 5d, and 4f orbitals. The hybridization is believed to be at its greatest for cerium, which has the lowest melting point of all, 795 °C. The lanthanide metals are soft; their hardness increases across the series. Europium stands out, as it has the lowest density in the series at 5.24 g/cm and the largest metallic radius in the series at 208.4 pm. It can be compared to barium, which has a metallic radius of 222 pm. It is believed that the metal contains the"
"are as follows: A=8.87Å, B=5.64Å, C=11.01Å, α=90˚, β=107.81˚, γ=90˚ Gallium is the lightest Group 13 metal with a filled d-shell, and has an electronic configuration of (Ar 3d10 4s2 4p1) below the valence electrons that could take part in d-π bonding with ligands. The somewhat high oxidation state of Ga in Ga(III)Br, low electronegativity, and high polarizability allow GaBr to behave as a ""Soft Acid"" in terms of the Hard-Soft-Acid-Base (HSAB) theory. The Lewis acidity of all the Gallium Trihalides, GaBr included, has been extensively studied thermodynamically, and the basicity of GaBr has been established with a number of donors."
"of any of the 118 known elements, lower only than bohrium (37.1 g/cm), meitnerium (37.4 g/cm) and hassium (41 g/cm), the three following elements in the periodic table. In comparison, the densest known element that has had its density measured, osmium, has a density of only 22.61 g/cm. This results from seaborgium's high atomic weight, the lanthanide and actinide contractions, and relativistic effects, although production of enough seaborgium to measure this quantity would be impractical, and the sample would quickly decay. Seaborgium is the fourth member of the 6d series of transition metals and the heaviest member of group 6"
"(not avgas), and laboratory cultures can degrade aluminium. However, these life forms do not directly attack or consume the aluminium; rather, the metal is corroded by microbe waste products. Aluminium Aluminium or aluminum is a chemical element with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic and ductile metal in the boron group. By mass, aluminium makes up about 8% of the Earth's crust; it is the third most abundant element after oxygen and silicon and the most abundant metal in the crust, though it is less common in the mantle below. The chief ore of"
"so low-carbon steels are the best choice, for example as structural steel. The density of mild steel is approximately 7.85 g/cm (7850 kg/m or 0.284 lb/in) and the Young's modulus is . Low-carbon steels suffer from ""yield-point runout"" where the material has two yield points. The first yield point (or upper yield point) is higher than the second and the yield drops dramatically after the upper yield point. If a low-carbon steel is only stressed to some point between the upper and lower yield point then the surface develops Lüder bands. Low-carbon steels contain less carbon than other steels and"
"a silvery-grey metal with a Mohs hardness of 5.5, and a standard atomic weight of 95.95 g/mol. It has a melting point of ; of the naturally occurring elements, only tantalum, osmium, rhenium, tungsten, and carbon have higher melting points. It has one of the lowest coefficients of thermal expansion among commercially used metals. The tensile strength of molybdenum wires increases about 3 times, from about 10 to 30 GPa, when their diameter decreases from ~50–100 nm to 10 nm. Molybdenum is a transition metal with an electronegativity of 2.16 on the Pauling scale. It does not visibly react with"
"Osmium Osmium (from Greek ὀσμή ""osme"", ""smell"") is a chemical element with symbol Os and atomic number 76. It is a hard, brittle, bluish-white transition metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element, with an experimentally measured (using x-ray crystallography) density of . Manufacturers use its alloys with platinum, iridium, and other platinum-group metals to make fountain pen nib tipping, electrical contacts, and in other applications that require extreme durability and hardness. The element's abundance in the Earth's crust is among the rarest."
"occurred along with it in its salts, he named it from the Ancient Greek ""λανθάνειν"" [lanthanein] (lit. ""to lie hidden""). Relatively pure lanthanum metal was first isolated in 1923. Lanthanum is the third-most abundant of all the lanthanides, making up 39 mg/kg of the Earth's crust, behind neodymium at 41.5 mg/kg and cerium at 66.5 mg/kg. It is almost three times as abundant as lead in the Earth's crust. Despite being among the so-called ""rare earth metals"", lanthanum is thus not rare at all, but it is historically so named because it is rarer than ""common earths"" such as lime"
"are smelted using carbon as a reducing agent. Some metals, such as aluminium and sodium, have no commercially practical reducing agent, and are extracted using electrolysis instead. Sulfide ores are not reduced directly to the metal but are roasted in air to convert them to oxides. Metals are present in nearly all aspects of modern life. Iron, a heavy metal, may be the most common as it accounts for 90% of all refined metals; aluminium, a light metal, is the next most commonly refined metal. Pure iron may be the cheapest metallic element of all at cost of about US$0.07"
"quickly begins to tarnish as it reacts with air. It is soft enough to be cut with a knife and it is the second least dense element. Potassium has a relatively low melting point; it will melt just by putting it under a small open flame. It also is less dense than water, and can, in turn, float. Calcium (Ca) is the second element in period 4, between potassium and scandium. An alkali earth metal, calcium is almost never found in nature due to its high reactivity with water. It has one of the most widely known and acknowledged biological"
"stable metals; this is exceeded only by darmstadtium, roentgenium, and copernicium among the superheavy metals. The [Rg(HO)] cation is expected to be the softest among the metal cations. Due to relativistic stabilisation of the 7s subshell, roentgenium is expected to have a full s-subshell and a partially filled d-subshell, instead of the free s-electron and full d-subshell of copper, silver, and gold. On the group 12 transition metals (zinc, cadmium and mercury), Smith observed that, ""Textbook writers have always found difficulty in dealing with these elements."" There is an abrupt and significant reduction in physical metallic character from group 11"
"one of the least abundant elements in the universe; only about % of all matter in the universe is europium. Europium is a ductile metal with a hardness similar to that of lead. It crystallizes in a body-centered cubic lattice. Some properties of europium are strongly influenced by its half-filled electron shell. Europium has the second lowest melting point and the lowest density of all lanthanides. Europium becomes a superconductor when it is cooled below 1.8 K and compressed to above 80 GPa. This is because europium is divalent in the metallic state, and is converted into the trivalent state"
"Mild steel (iron containing a small percentage of carbon, strong and tough but not readily tempered), also known as plain-carbon steel and low-carbon steel, is now the most common form of steel because its price is relatively low while it provides material properties that are acceptable for many applications. Mild steel contains approximately 0.05–0.25% carbon making it malleable and ductile. Mild steel has a relatively low tensile strength, but it is cheap and easy to form; surface hardness can be increased through carburizing. In applications where large cross-sections are used to minimize deflection, failure by yield is not a risk"
"list and (unless otherwise stated) guide the remainder of the article. Metalloids meeting the applicable criteria–arsenic and antimony for example—are sometimes counted as heavy metals, particularly in environmental chemistry, as is the case here. Selenium (density 4.8 g/cm) is also included in the list. It falls marginally short of the density criterion and is less commonly recognised as a metalloid but has a waterborne chemistry similar in some respects to that of arsenic and antimony. Other metals sometimes classified or treated as ""heavy"" metals, such as beryllium (density 1.8 g/cm), aluminium (2.7 g/cm), calcium (1.55 g/cm), and barium (3.6 g/cm)"
"divalent metals. They have the lowest melting points among all transition metals. Zinc is bluish-white and lustrous, though most common commercial grades of the metal have a dull finish. Zinc is also referred to in nonscientific contexts as ""spelter"". Cadmium is soft, malleable, ductile, and with a bluish-white color. Mercury is a liquid, heavy, silvery-white metal. It is the only common liquid metal at ordinary temperatures, and as compared to other metals, it is a poor conductor of heat, but a fair conductor of electricity. The table below is a summary of the key physical properties of the group 12"